|
| |
Answers :
| CN No. |
Answers |
| CN 110 |
1. The number of turns of the coil. 2. The
amount of electric current. 3. type of core used |
| The polarity of the battery does not affect the
strength of an electromagnet. |
| The North and South poles will be reversed if
you reverse the connection to the battery. |
| CN 111 |
Applications : flag poles, cranes, lifts, cars. |
| Effort = 0.5Kg (or 500g) / Effort moves by 20cm |
| CN 112 |
Gear ratio : 4:1 |
Change the speed, Change the direction of
rotation and transfer turning movement from one place to another. |
Applications : bicycle, car gear box, toy cars,
tape recorder, mechanical clock, etc.
A : faster, 1:1.5, B : faster, 1:3, C : same, 1:1 |
| CN 113 |
1). A. nothing. B. Motor turns. C. Motor turns
in reverse direction. D. Nothing |
| 2). series, 3V |
| colour the car frame, add stickers, make a
chassis or add a light bulb. |
| CN 114 |
Battery |
Switch |
Motor |
| CN 115 |
Battery |
| Two batteries in series |
| Switch |
| Motor |
| CN 116 |
2). 40 turns |
3). D,B,C,A |
A= 1:1.5, B= 1.7:1, C= 1:1, D= 2.5:1 |
| CN 117 |
(1) will light, (2) Will not light, (3) Will
not light, (4) will light |
| CN 118 |
1). will not light up. 2.1) light up, 2.2) will
not light up. 3). parallel : remain the same, light up. series : dim, not
light up. 4). series : off/off/off/on. parallel : off/on/on/on |
| CN 119 |
Top diagram |
Middle diagram |
Bottom diagram |
| sw A |
sw B |
Bulb A |
Bulb B |
sw A |
sw B |
Bulb A |
Bulb B |
sw A |
sw B |
Bulb A |
Bulb B |
| Open |
Open |
off |
off |
Open |
Open |
off |
off |
Open |
Open |
off |
off |
| Open |
Closed |
off |
off |
Open |
Closed |
off |
off |
Open |
Closed |
on |
on |
| Closed |
Open |
on |
off |
Closed |
Open |
off |
off |
Closed |
Open |
on |
off |
| Closed |
Closed |
on |
on |
Closed |
Closed |
on |
on |
Closed |
Closed |
on |
off |
| CN 120 |
A : effort, B : fulcrum, C : load |
| CN 121 |
reduce |
Applications : screw driver, tap, door lock,
spanner, steering wheel, etc |
2Kg |
| CN 122 |
1). The motor turns slower. 2). A:
anti-clockwise, 15 rounds. B: clockwise, 10 rounds. D: clockwise, 10
rounds. E : anti-clockwise, 20 rounds. 3). System A : cannot. System B :
can |
| CN 123 |
1). A, B & D. 2). A: anti-clockwise, 1
round. B: anti-clockwise, 1 round. 3). System A : cannot. System B : can |
| CN 135 |
fans, airplanes, ships, hovercrafts,
helicopters, etc. |
| CN 207 |
40. |
40:1, 2:1 |
Gear system ratio = 80:1 |
| CN 505 |
1). 2.25m/s |
2). 675m |
3). 3packs |
4). 40, 10, 32.97m |
| CN 506 |
a). 80 cars, 720 cars/day |
b). 2 workers |
c). $158.40 |
| CN 507 |
1a). 50% b). 1h40m, 2h |
2). 260m |
3). 500 cars |
4). 350 cars |
BACK
|
